Hadith 2:251

Narrated Anas bin Malik

Once the Prophet (p.b.u.h) entered the Mosque and saw a rope hanging
in between its two pillars. He said, "What is this rope?" The people
said, "This rope is for Zainab who, when she feels tired, holds it (to
keep standing for the prayer.)" The Prophet said, "Don't use it.
Remove the rope. You should pray as long as you feel active, and when
you get tired, sit down."